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Bone marrow chimera mice dies 8 weeks post injection - (Jun/11/2013 )

Hello guys,

I made a bone marrow chimera mice and they died 8 weeks later after irradiation and BM cell injection.

Briefly, 8 weeks old B6 mice were irradiated at 950Rads and BM cells from CD45.1 B6 mice and CD45.2 KO mice of my interest were 1:1 mixed and injected retro-orbitally.

They were given acidified and baytril treated water for 4 weeks and then changed to normal sterile water.

After 8 weeks I found 5 of 6 dead and the last one very weak. It had weight loss, hunched back, and partially discolored hair.

There was no gross internal organs as far as I saw and both CD45.1 and CD45.2 cells from LNs and spleens (they were way smaller than it should be but I am not sure it was due to weight loss or lack of cell proliferation) were observed so I assume BM cells were transfered well as anticipated.

Do you have any idea what could go wrong?

Thanks.

-Wonyong-

Radiation sickness - 950 rads will kill a most adult humans, let alone a small mouse.

-bob1-

bob1 on Wed Jun 12 10:31:49 2013 said:


Radiation sickness - 950 rads will kill a most adult humans, let alone a small mouse.


For bone marrow cell depletion, 900~1000 Rad of radiation is routinely used for C57BL/6, or at least all the protocols I fould say so.

They say it is lethal dose, meaning that mice die within 2 weeks without bone marrow transfer.

Also, rad is the absorbed energy of radiation per kg, so 950 rad of radiation absorbed by only 20g mice would not kill a person. Radiation therapy uses 2~8 krad.

-Wonyong-

Wonyong on Wed Jun 12 12:27:52 2013 said:


bob1 on Wed Jun 12 10:31:49 2013 said:


Radiation sickness - 950 rads will kill a most adult humans, let alone a small mouse.


For bone marrow cell depletion, 900~1000 Rad of radiation is routinely used for C57BL/6, or at least all the protocols I fould say so.

They say it is lethal dose, meaning that mice die within 2 weeks without bone marrow transfer.

Also, rad is the absorbed energy of radiation per kg, so 950 rad of radiation absorbed by only 20g mice would not kill a person. Radiation therapy uses 2~8 krad.

As you say - absorbed dose - so 950 rads given to a whole body for a human is pretty close to a lethal dose... radiation therapy is locally applied for the doses you suggest. Radiation therapy or exposure typically results in lesions on the skin, reduction in the size of some of the organs and loss or changes in the hair. It would seem that your transplant is partially effective - have you tried giving it intravenously rather than retro-orbitally? What about immunosupressive drugs - graft vs host disease could be a problem here too.

Incidentally, as you probably know, rad is no longer the unit usually used for this sort of thing, instead the SI unit of Gray (Gy) is preferred.

-bob1-